Originally built in 1774 by Thomas Johns, a colonel during the American Revolution, and Thomas Richardson, a prominent Georgetown merchant, large flour mills stood on this site along Rock Creek until the 1870s. Richardson, appointed by General George Washington to provide food for the American troops, supplied them from this mill site. Josiah Henson, a celebrated evangelist and model for Harriet Beecher Stowe's Uncle Tom's Cabin, received his Christian baptism here while still enslaved on the nearby Riley Plantation. The mills continued to produce flour throughout the nineteenth century, but ceased operating after the arrival of the Metropolitan Branch of the Baltimore and Ohio Railroad. Members of the Washington Duvall family were the last owners.